The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without payment of any royalties thereon or therefor.
The present invention relates to an aircraft load cell shoring. More specifically, but without limitation, the present invention relates to an aircraft load cell shoring for engine-on spar cap insertions and complete replacements or wing repairs.
Aircraft often require spar (specifically aft spar cap) repair or complete replacement of the spar (or spar cap) due to major damage. A spar is typically defined, but without limitation, as one of the principal structural members in an airfoil, especially in a wing, running from tip (outer end of an airfoil, such as a propeller blade or wing) to tip or from root (base of an airfoil where it joins the body or fuselage of an aircraft) to tip. A spar cap is typically defined, but without limitation, as a continuous wing piece that runs from wing root to wing tip, and is a support structure of the wing box. The spar cap also supports air and structural loads.
To perform a spar or spar cap repair or a complete replacement, the affected wing must be in an unloaded condition. A wing in an unloaded condition is typically a condition where the wing does not bear, support, sustain or hold any pressure, encumbrances or weight. The spars and/or spar caps are typically removed by removing the fasteners that attach the spars or spar caps to the aircraft or airfoil. Any load, such as the weight of the engines on the wing or the weight of the wing itself, can cause shifting of the airfoil parts when the fasteners are removed from the spar and/or spar caps. Placing the airfoil parts back in their original locations is often difficult and time consuming. Therefore, it is very important that the wing be in an unloaded condition during repair or replacement of spars or spar caps.
Conventional methods require removal of engines to repair or replace spars, spar caps and/or wings. Removal of an aircraft engine is time consuming and expensive. Furthermore, to reinstall and rerig the aircraft engine back to its original installation is time consuming, expensive and difficult, especially in military aircraft which often have other apparatuses and systems (such as weapon, surveillance, anti-radar systems, navigation systems) working in concert and in communication with the aircraft engine.
For the foregoing reasons, there is a need for an aircraft load cell shoring that places a wing in an unloaded condition without removal of attached aircraft engine(s) and allows easy repair or replacement of spar or spar caps. Information relevant to attempts to address these problems can be found in U.S. Pat. Nos. 4,469,307, 4,717,094, and 5,810,287. (None of these patents are admitted to be prior art with respect to the present invention.) However, each of these references suffers from one of the above listed disadvantages.
The present invention is directed to an aircraft load cell shoring that satisfies the needs listed above and below.
It is an object of the present invention to provide an aircraft load cell shoring for use with a load cell mounted on an aircraft jack. It is a further object of the present invention to provide an aircraft load cell shoring that includes a load cell adapter and a shoring contour assembly. The shoring contour assembly may support the aircraft engine at one, two or several specific locations. The load cell adapter is disposed above the load cell, and the load cell is mounted on the aircraft jack. The shoring contour assembly has a fixed receptacle located at the shoring contour assembly bottom portion. The load cell adapter communicates with the fixed receptacle, while the fixed receptacle is positioned so that the aircraft jack can be located at the center of gravity of the aircraft engine and enclosed portion of the wing.
It is also an object of the present invention to provide an aircraft load cell shoring that places a wing in an unloaded condition without removal of any attached aircraft engine(s).
It is another object of the present invention to provide an aircraft load cell shoring that eliminates the significant cost and time of removing and reinstalling aircraft engines for spar, spar cap, and wing insertions, replacements, or repairs.
It is an object of the present invention to provide an aircraft load cell shoring which allows quicker turn around time for removal or replacement of a spar, specifically of an aft spar cap.
It is an object of the present invention to provide an aircraft load cell shoring that has the ability to measure the force that is actually being applied with the shoring.